Barton has vowed to appeal against the punishment - but at the same time said he wants to avoid becoming embroiled in a tit-for-tat war after the club leaked a list of grievances to a local newspaper.

The situation has moved quickly for Barton this week, who was placed on the transfer list - for no fee - on Monday afternoon and then promptly ostracised from the rest of the squad and told to train on his own.

Tottenham, Arsenal and Liverpool are all said to be considering a move for a player who has rebuilt his career on Tyneside after well-documented troubles both on and off the pitch.

The player's agent, Willie McKay, says there is a total of six clubs who have already indicated an interest - with two of those clubs in the Champions League this season. It is also claimed a Championship club, West Ham, and four foreign clubs want him.

Barton has voiced his anger at the club on Twitter for weeks after he was told he would not be offered a new contract and Kevin Nolan was sold to the Hammers.

On Tuesday, the Newcastle Chronicle listed his alleged misdemeanours which included the player arguing with a team-mate prior to a Premier League game at the end of last season, as well as other rows.

The Chronicle believes the final straw was not friction with other squad members, or his outbursts on Twitter, but a refusal to shake the manager Alan Pardew's hand when he had been stripped of the captaincy for Sunday's pre-season game at Leeds United. Within hours of that game he has been transfer listed.

The club feels Barton is a potential bad influence on the squad's younger players, and his actions create a poor impression for new signings and potential transfer targets.

Barton responsed to the newspaper article by tweeting: "If the club want to put out all these false statements via the Chronicle, then let them do that. Everyone here knows, I speak the truth..... I also have too much respect for my teammates and the fans, to get in a tit for tat war with them. I have too much self-worth and dignity."

But it did not take Barton long to follow up with: "Ha ha the inevitable, 2 weeks wages fine has just arrived. Needless to say it shall be appealed forthwith. #kickingamanwhilsthesdownha"